Power-hammer



(No Model.)

P. G. BROOKSBANK.

POWER HAMMER. No. 485,169. Patented Nov. 1, 1892.

N EN Tu /pdwwk 5 bm14m Uivrrno TATES PATENT OFFICE.

FREDERICK O. BROOKSBANK, OF CLEVELAND, OHIO.

POWER-HAMMER.

SPECIFICATION forming part of Letters Patent No. 485,169, dated November1, 1892.

Application filed October 5, 1891.

To all whom it may concern.-

Be it known that I, FREDERICK C. BRooKs- BANK, a citizen of the UnitedStates, residing at Cleveland, in the county of Cuyahoga and State ofOhio, have invented certain new and useful Improvements inPower-Hammers, of which the following is such a full, clear, and exactdescription as will enable others skilled in the art to which itappertains to make and use the same.

My invention, hereinafter described, was especially designedfor useinconnection with the class of power-hammers now well known in the marketas Hackney hammers, which are shown and described in two patents grantedDecember 11, 1888, and numbered 394,483 and 394,484, to Jacob B. Perkinsand myself as assignees of Gilbert Glossop. The invention is, however,applicable to any power-hammer having a reciprocating tup operatingbetween fixed guides and a friction brake-block which may be forcedagainst said cup with greater or less pressure for the purpose ofretarding the movement of said tup or of stopping it altogether.

The invention as broadly claimed is also applicable to any mechanicalcontrivance containing a reciprocating part movable be tween fixedguides which it is desirable to stop or check by means of afriction-brake.

The objects of my invention are, first, to provide novel means wherebyafriction brakeblock may be positively moved against a movable part forthe purpose of applying more or less friction thereto; second, toprovide novel means whereby wear on the brakeblock maybe compensated forand the device maintained in an operative condition for a long timewithout replacing any of the parts.

In the drawings, Figure 1 is a front elevation of the lower part of apower-hammer containing my invention. Fig. 2 is a View on an enlargedscale in section on the line 2 2 in Fig. 1 through one of the standards,the tup, and brake mechanism; and Fig. 3 is a detached front view of thepressure-block, rockshaft, and eccentric.

Referring to the parts by letters, A A represent the standards of apower-hammer, and B the tup, which is caused to reciprocate in avertical path between said standards by Serial No. 407,730. (No model.)

suitable mechanism. The meeting faces of the standards and tup areprovided with tongues and grooves, by which the tup is guided. Set intothe face of one of the standards is a friction brake-block F, having agroove f, similar to the groove in the standard above and below it. Asthis brake-block is forced with more or less pressure against the tup,it either stops the movement of said tup altogether or retards itsmovement. The length of the brake-block is such that it always remainsin contact with some part of the tup. Behind the brake-block a recess 0bis formed in the standard, which recess is slightly larger than thepressure-piece D, which operates therein.

The pressure-piece D is in the form shown square, and it is providedwith a transverse cylindrical orifice placed eccentric to its foursides-that is to say, the perpendicular distance from any side to thenearest point in the periphery of the orifice is either greater or lessthan the distance similarly measured between any other side and saidorifice.

0 represents a rock-shaft journaled in the standard A, and c aneccentric rigid therewith, which is nicely fitted into the cylindricalorifice in the pressure-piece.

E represents a lever keyed or otherwise rigidly secured to one end ofthe shaft 0, by means of which it may be rocked. One arm e of the levermay be used as a hand-lever, while the other arm 6 is connected by therod g with treadle G. Springs g g, each connected at one end with thetreadle and at the other with the standards, exert a continuous force tolift the treadle and through the intermediate mechanism to apply thebrake, as

will be hereinafter pointed out.

the side dot the piece D which is nearest the orifice is placed next thebrake-block. When said brake-block has been worn down so that it nolonger acts efficiently, the piece D is removed and turned one-quarteraround on the eccentric 0, so that the side (1' thereof which is nextthickest (between the outside and the orifice) bears against saidbrakeblock. In due time the next-thickest side 01 may be placed againstthe brake-block, and finally the side 01 maybe so placed. Thus the sameparts may be used without any other change in their relative positionthan those above pointed out until a very considerable part of thebrake-block has been worn away. Having thus described my invention, WhatI claim as new, and desire to secure by Letters Patent, is- V 1. In apower-hammer, the combination of the standards, reciprocating tup, and afriction brake-block set into one of said standards at the side of thetup with a rectangular pressure-piece set into the standard behind saidbrake-hlock and having an eccentrically-placed cylindrical orifice, arock-shaft journaled in said standards, and an eccentric secured theretopassing through said orifice, substantially as'and for the purposespecified.

2. The combination of a reciprocating part, its guides, and a frictionbrake-block bearing against'said part with a square pressure-piecehaving a transverse cylindrical orifice placed at unequal distances fromall four s1des, a rock-shaft, and an eccentric secured to saidrock-shaft and passing through said or fice, substantially as and forthe purpose specified.

3. The combination of a reciprocating part, its guides, and a frictionbrake-block bearing against said part With a rectangular pressore-piecebearing against the rear side of said brakerblock and having acylindrical orifice set at unequal distances from all four s1des, arock-shaft, and an eccentric secured to said rock-shaft and passingthrough said orifice, substantially as and for the purpose specl tied.

FREDERICK O. BROOKSBANK.

Witnesses:

E. L. THURSTON, M. S. INGHAM.

